Radiant heaters

ABSTRACT

An infra-red radiant heater comprises a combustion chamber defined by two oppositely-directed frusto-conical members joined together at their bases. A burner is supported by one of the members and the other member has radial corrugations, this latter member being heated by the combustion gases and serving as an emitter of infra-red radiation. The corrugations direct the combustion gases towards a vent.

United States Patent 1191 'Brola Aug. 6, 1974 RADIANT HEATERS 3,716,0422/1973 Smith 126/92 R [76] Inventor: Gabriel Brola, 4, Avenue VictorFOREIGN PATENTS OR APPLICATIONS Hugo Nogem-sur-Mame, 560,556 9/1957Belgium 126/92 R France 1,127,334 7/1955 France 126/92 B 22 F'] d: 22,1973 l 1 l e Jan Primary Examiner-Carroll B. Dorlty, Jr. PP 325,605Assistant Examiner-Larry I. Schwartz Attorney, Agent, or Firm-Eyre, Mann& Lucas [30] Foreign Application Priority Data Mar. 6, 1972 France 72.O8554 [57] ABSTRACT An infra-red radiant heater comprises a combustion[52] U.S. Cl. 126/92 B, 431/328 chamber fined by two oppos te y-directedfrusto- 51 1m. (:1. F24c 3/04 conical members joined together at theirbasee- A [581 Field of Search 126/92 B, 92 R; 431/328, burner s supp e ye of the members and the 431/329 other member has radial corrugations,this latter member being heated by the combustion gases and serving [56]Refer Cit d as an emitter of infra-red radiation. The corrugationsUNITED STATES PATENTS direct the combustion gases towards a vent.

3,561,422 2/1971 Colin et a1. 431/328 4 Claims, 2 Drawing Figures Pmmmmsslam SHEEY 2 0F 2 RADIANT HEATERS FIELD OF THE INVENTION The presentinvention relates to infra-red radiant heaters.

SUMMARY OF THE INVENTION According to the present invention, there isprovided in an infra-red radiant heater, a burner, two generallyfrusto-conical members facing in opposite directions and joined togetherat their bases, said frusto-conical members defining a combustionchamber, and vent means, one of said frusto-conical members supportingthe burner, and the other frusto-conical member having corrugationsarranged to direct the combustion gases towards the vent means.

The burner can be fed with liquid or gaseous fuel. When the heater is inaction, the combustion gases play upon the said other frusto-conicalmember, the wall of which constitutes a heat-exchange surface andconstitutes an emitter of infra-red radiation.

BRIEF DESCRIPTION OF THE DRAWINGS An embodiment of the invention willnow be described, by way of example only, with reference to theaccompanying diagrammatic drawings, in which:

FIG. 1 is a longitudinal section of a heater in accordance with theinvention; and

FIG. 2 is a transverse section of the heater taken at two differentlevels.

DESCRIPTION OF THE PREFERRED EMBODIMENT The radiant heater shown in thedrawing comprises a combustion chamber 1 defined by lower and upperfrusto-conical members 2 and 7 facing in opposite directions and joinedtogether at their bases.

The lower member 2 has radial corrugations 3 the dimensions and pitch ofthe corrugations increasing towards the base of the member 2. Thecorrugations 3 are of channel section having divergent walls.

A profiled lining wall 4 is welded within each corrugation and extendsalong part of the length thereof, the walls 4 defining with thecorrugations 3, radial passages 21 for directing the combustion gases;these passages constitute a convector for effecting heat-exchangebetween the gases and the walls of the lower member 2.

The lower member 2 is welded by its base to an annular collector 5 theunderside of which contains holes 6, equal in number to the corrugationsin the lower member 2; each of the holes 6 in the collector 5 liesopposite one of the radial passages 21 in the lower member 2. 5

The upper member 7 is likewise welded at its base to the collector 5.The wall of the member 7 incorporates a number of concentric ridges 8 tostrengthen it against deformation and the inner face of the member 7 islined with a layer of non-rigid refactory material 9.

The combustion-chamber assembly thus formed is fixed by means of adetachable flange 14 to a circular plate 15. A metal reflector 16,having a highly polished inner face, is mounted on the periphery of theplate 15 and constitutes the reflector of the heater.

In its central portion the plate 15 has an opening over which isarranged the combustion tube 22 of a burner 17. A fan of the burner 22is mounted on a door 18 which is attached by hinges 19 to the plate 15.By opening the door 18 the burner fan'is displaced to give access to thecombustion system located in the combustion tube. A fuel oil pump 20,for feeding liquid fuel to the burner, is coupled to the fan motorshaft.

The infra-red radiant heater described operates as follows:

When the burner 17 is in operation, the flame leaving the combustiontube 22 passes into the combustion chamber 1 of the heater. Thehigh-temperature combustion gases pass downwardly in the chamber 1 andarrive at the inner surface of the lower member 2. The gases then passupwardly through the passages 21 towards the base of the member 2; thegases enter the collector 5 via the holes 6 and are discharged toatmosphere through a pipe 10.

The flame serves to heat the lower member 2 by radiation and also byconvection through the radial passages 21, through which the combustiongases pass. Further, radiant heat transmitted to the upper members 7 isreflected by the refractory lining 9 to the lower member 2, so thatpractically the whole of the heat content of the flame is transmitted tothe lower member 2.

The wall of the member 2 is thus raised to a high temperature and theamount of infra-red radiation produced is governed by that temperature.The relatively small amount of radiant heat emitted from the upper coneis reflected by the reflector 16 over an angle of about 140.

The radial corrugations 3 in the lower member 2 determine the path ofthe combustion gases in the combustion chamber, and also facilitate theemission of the infra-red radiation. When the lower member is raised toa high temperature by natural convection, a fraction of the heat isabsorbed by the surrounding air, the result of this being a naturalcirculation of air around the member 2. The hollows of the corrugations,not being swept by that air circulation, are consequently less cooled,whereby the temperature of the member 2 is higher. By virtue of thesecorrugations, the loss of heat by natural convection is reduced by morethan 50 percent, so that the emission of infrared radiation is increasedby about to percent.

In the heater particularly described high-intensity infra-red radiantenergy can be transmitted to a long distance away with the result thatthe heater is particularly useful for heating large industrial orcommercial premises such as, for example, stock-yards or swimmingpoolsand, in general, places where heating cannot be provided by hot-airconvection.

What is claimed is:

1. In an infra-red radiant heater,

a burner,

two generally frusto-conical members facing in opposite directions andjoined together at their bases, said frusto-conical members defining acombustion chamber, and

vent means, one of said frusto-conical members supporting the burner,and the other frusto-conical member having corrugations arranged todirect the combustion gases towards the vent means.

2. A heater as claimed in claim 1, in which the corrugations are ofchannel section having divergent walls.

3. A heater as claimed in claim 1, further comprising annular collectormeans, said collector means joining together the said frusto-conicalmembers and being connected to the vent means, and said collector meanshaving holes opposite the corrugations in the said other of thefrusto-conical members.

1. In an infra-red radiant heater, a burner, two generallyfrusto-conical members facing in opposite directions and joined togetherat their bases, said frustoconical members defining a combustionchamber, and vent means, one of said frusto-conical members supportingthe burner, and the other frusto-conical member having corrugationsarranged to direct the combustion gases towards the vent means.
 2. Aheater as claimed in claim 1, in which the corrugations are of channelsection having divergent walls.
 3. A heater as claimed in claim 1,further comprising wall means closing each corrugation for at least partof its length, said wall means defining with the corrugation a ragialcirculation passage communicating with the vent means.
 4. A heater asclaimed in claim 1, further comprising annular collector means, saidcollector means joining together the said frusto-conical members andbeing connected to the vent means, and said collector means having holesopposite the corrugations in the said other of the frusto-conicalmembers.